Inflatable tire



B. G. 'GOBLE INFLATABLE TIRE Feb. V24. 1925.

Filed March 17, 1921 2 sneetssheet 1 Feb. 24. 1925. l 1,527,862 B. G. GOBLE INFPATABLE, TIRE 2 sheets-sheet 2 Filed March 17, 1921 `placed With-in the casing.

Patented Feb. 24, 1925.

UNITED stares Lazise-z naar e; sonnen, or Tense, Ontariens;

ruste-TABLE TIRE.

Application aie'd Marcar?, 19'2'1. serial Nb.' 453,0o`i.

To all whom z'zmafz/ concern.' Y

Be it lrnoivn that l, BnnrGr.l Cronin, a citizen of the United States" of America, residing` at Tulsa, in the county of 'llulsa and State of' Oklahoma, have invented certain new vand useful Improvements?i'n'ln# iatable Tires, of which the follmving; is a specilication. o

rlhis invention relates to certain new aiid useful improvements in iniiatablet' 41esand more particularly. tothe inner tubes therefor of the4 style, thev material oiisvhic'h is under compression, instead-'lof Aunder tension, when the tube is encasedand iniiated.

Inner tubes of this `type have been provided with one or more annularcontinuous depressions or folds, .and the eXternal diam'- eterot' the tube is rgreater'than thefinternal diameter of the casing with lWliiclrit' ,isv to beiused7 so that when the tube is iilled'with air under pressure,said'tube is forced into snug Contact with the innerv face VVof vthe cas ing throughout', and the tube -iS thereby placed under transverse compression, Tubes oli this character'` which have heretoifore been devised, have been extreln'iely'hard tof-place Within the casingthisibeing caused in some instances by the provision, in'additionito side folds or depressions; of, a tread toldV or Vdepression so that the folds'arewne'cessarily based upon abrupt curvatures' which *cont biney to provide aso'mevvhat truss-like structure.A niakingtheA tube veryrigid s o thatit Willfnot readilysgive or Hexitvh'en'being This rigidity'is pronounced When it is considered that the compression type of tube isfnecessarily of considerable thickness of material;

In addition tothe ltactthat the provisionl ot Vmore than two tolds Ain `a tube of this character?, provides undesirable' rig'gidityl 'of the tube, it also gains no additional coinpression because of the tact that at least one of the three folds may` not "be practically made of suhcient depth to Ygain such -`additional :compression In other Words, the provision of the foldsis to primar-ily obtain argreaterlexternal diameter for the 'tube ,than the' internal diameter ot thevcasing, and in order to accomplishthis,` the r depth of the folds must be greatenoughfto Vgive the-tube a greater length at the o'ldthanthe corresponding` surface on the inside the casing. There 'is not suicienthroom for three sufficiently deep. 4folds in a tube ofthis character unless the oldsare based upon curves so abrupt as to ma'lreina'nutacture of the saine entirely impractical, the manu@ facture of a tube of uniform thiclness`be ing at least extremely' hard to acconj'iplish where yvery abruptl curves` are encountered.

In'such cases Where only a singlelanda tread depression or fold has been used', the tube has a normal circular cross sebtion, and extraneous means is relied upon for holding the tube'in an abnormal condition Withfthe 'fold portion tending toprnve' outwardly into {iatcontact with the inner face ofth'e casing when the tube is released. By the use of such holdinglin'eans, the tube is forced into a very broad cross sectional dimensin, andthe tubeis then ofv'ery abrupt curvature at thesidesfandlwider than thel casing so that placement of such a tube Wit' in/'the casing entails considerable skill 'and' arduous labor. Y

lt has been also proposed 'tofprovide -a pair of folds,'onelocated at eacliside of the tread portionof thecas'ing but outwardly of the axial center lineof the tube." Ithajsrbeen liouiichlhoweveig that a'tube'so' constri'uzted does not haveiriuch'more HeXibility than' the beiore'nient'i'dned prior art tubeiandtherefore the operation'of placingthe tube Within the 'casing'is 'also 'tedious'` l i lnnaddition to this, when the folds are providedentirely out- Wardly of the Y axial center vline of the' i tulie,

the fold' portions "of the tu e' are necessarily placed under circuniere tialfystretch jvheifi inflated to "such anextent alsfto be detrimental under running conditions;V .i r v A i ln 'the present inventidnithe above detects are overcome by" the vprovision of a coin pression tufee uioldeld to 'hays afno'rmal form with only tivo depressions or loldslocated at the sides of the tube and'fiiitersecting the axial center line fot the tube so that the "tube is highly flexible Vfor being readily'V placed Within theicasingand that no material circu'n'ifer'ential stretch results, the little lcircumferential stretch in,I the foldsv` thatldoes take place being` entirely away troni the tread portion oth the ytube ivhe're .punctures most ordinarily occur. Also ,f the'folds` oi lthe present tube are based uponflong symmetrical curves "instead of abrup'tfones so that the flexibility of the tube isjther'eb'y insides of the curves, is reduced to aymi`nimum, when the tube is changed in' shape yby iniiatin.i i l l The present inveutionalso contemplates lenhanced and stretchingoi thetube at the of the tubs is thereby not impaired.

molding of the tube so as to normally be spaced from the rim and the bead portion of the casing for permitting placement of the tire upon the rim and insertion of the fastening rings of the rim with much greater ease.

With the above general objects in view, and others that will become apparent as the nature of the invention is better understood, the same consists in the novel form, combination and arrangement of parts hereinafter more fully described and shown in the accompanying drawings, in which like ref-erence characters designate corresponding parts throughout the several views.

In the drawings,

Figure 1 is a transverse section through tire and rim and showing the present inner tube seated within the casing prior to the admission of air under pressure to the interior of the tube,

Figure 2 is a view similar to Figure 1 showing the inner tube of the latter figure inflated by air un-der pressure so as to place the tube under compression, this Figure 2 being drawn on a smaller scale,

Figure 3 is a view similar to Figure 1 of a modified form of the invention, and

Figure 4 is a view similar to Figure 2 of the device shown in Figure 3. I

Referring more in detail to the several views, and particularly to Figures 1 and 2, 5 indicates the present inner tube whose internal diameter is greater than the internal diameter of the casing 6 with which it is to be used, and whose circumferential length at its inner periphery as at 7, is normally greater than the circumferential length of the rim 8 which carries the tire, the difference in length at this point being suiiiciently great to leave a material space as at 9 between the inner periphery of the tube and the usual protecting band or flap 10 which is placed upon the rim so as to protect the inner portion of the tube from rust and other Vdifficulties normally encountered. The tube 5 is also molded at opposite sides of its inner periphery 7 so as to normally leave spaces as at 11 between the tube and the bead portions 12 of the casing 6 so that said bead portions may readily yield towardy each other for permitting ready insertion of the fastening rings 13 and 14 commonly found upon the conventional detachable or demountable rims now in use, and which fastening rings ordinarily are quite hard to place in position or to remove.

|The tube is also molded so that substantially its entire tread portion 15 conforms to the adjacent inner surface of the casing 6 so that no inward folds or fold is provided at the tread of the tube and the flexibility As clearly shown in Figure 1, the tubel 5 is molded with opposed annular folds or detersect the axial center line A--A of the latter and to be'entirely away from the tread portion of the tube, the folds 16being based upon long symmetrical curves calculated to give high iiexibility for permitting ready insertion of the tube within the casing.

The form of the invention shown in Figure 3 is similar to that shown in Figure 1 with the exception that the tread portion 15 of thek tube 5 is molded on an arc or curvature of lesser radius than that of the adjacent inner surface of the casing 6 so that if the tube 5 were actually centered within the casing as shown in Figure 8, a uniform spaceas at 17 would be left between the tread portion of the tube and the casing. This spacing at the tread portion is calculated to render insertion of the tube within the casing additionally easier. In'this form of the invention, the side folds are denoted by the numeral 16, the axial center line of the tube at AA, the inner periphery by 7', the rim by 8', the protecting ring by 10 and the space between the periphery 7 and the ring or band 10 by 9', and the fastening rings by 13 and 14. The spacing between the inner side portions of the tube and the bead portions of the casing are. indicated by the numeral 11 while the bead portions of the casing are indicated by the numeral 12. Thus it will be seen that the entire tube, if centered in the casing in deflated condition, would be entirely spaced from said casing and with this normal relative size and shape between the tube and casing, insertion of the tube in the casing may be easily accomplished.

As is usual in'this general type of tube, and as shown clearly in Figures Zand 4, the tube assumes a flat contact with the inner surface of the casing throughout when the tube is placed under iniiation pressure and when this takes place, the compression of the tube is had.

It is believed that the construction and operation kas well as the advantages of the present invention will 'be readily understood and appreciated by those skilled in the art. Reservation is made of the right to make such specific changes in contour and arrangement as may fall within the spirit and scope of the invention as expressed in t-he accompanying claims.

What is claimed as new is:

l. As a meansfor pneumatically supportinga casing or shoe for vehicle service, an inner tube formation having a normal definite and predetermined cross sectional contour when out of a shoe and Vfree from pressure application and a cross sectional coniiguration varied from such normal configuration when inflated within the shoe, said shoe formation having its walls of a thickness such as to maintain such normal configuration When free from pressure application to the formation, the normal configuration of such formation presenting the tread zone of the formation as of a curvature substantially complemental to the internal face of the tread zone of the shoe, such normal configuration presenting the side Walls of the formation as annular depressions, the depth of the depressions on a cross section of the formation being such as to cause the inner face of the depression Wall at the bottom of the depression to approach a pla-ne of the formation that extends parallel to a side of the formation When inflated and which extends central of the formation, the bottoms of the depressions on a cross section of the formation each intersecting a line extending approximately through the axis of the formation transversely7 of such plane, the Walls of each depression generally diverging from the depression bottom and joining the portions of the formation beyond the depression, the bottoms of the depressions and the joining portions extending on curved lines free from abrupt changes in direction,

whereby the formation is insertible Within the shoe-and the cross sectional Wall of the formation is inflatable to place it in facial contact With the positioned shoe, the depth of the depressions being such as to place the Wall material of the formation under compression in the direction of its cross seetional length and substantially throughout such length. Y

2. An inner tube formation of the type of claim l characterized in that the length of the radius producing the outer face of the tread zone of the formation is less than the length of the radius producing the inner face of the tread Zone of the shoe, whereby the formation When symmetrically positined Within the shoe prior to the formation inflation Will present a space of materialy extent between the opposing faces of the respective tread zones of the shoe and formation, iniation of the formation serving to eliminate such space and place the opposing face portions of the tread zones in facial contact.

In testimony whereof I affix my signature.

BERT G. GOBLE. 

